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#include <stdio.h> |
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#include <stdlib.h> |
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#include <string.h> |
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#include <errno.h> |
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#include <limits.h> |
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#include <sys/stat.h> |
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#include <time.h> |
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|
9 |
#include "config.h" |
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#include "imapfilter.h" |
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#include "pathnames.h" |
12 |
|
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#ifdef ENCRYPTED_PASSWORDS |
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#include <openssl/evp.h> |
15 |
#endif |
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|
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|
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extern unsigned int flags; |
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extern account_t *accounts; |
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extern char *home; |
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|
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#ifdef ENCRYPTED_PASSWORDS |
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extern char *passphr; |
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#endif |
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|
26 |
|
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int store_passwords(account_t ** accts); |
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|
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|
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/* |
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* Get password from user interactively. |
32 |
*/ |
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void |
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get_password(char *passwd, size_t pwlen) |
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{ |
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char *c; |
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|
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tty_noecho(); |
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|
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if (fgets(passwd, pwlen, stdin)) |
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if ((c = strchr(passwd, '\n'))) |
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*c = '\0'; |
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|
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tty_restore(); |
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|
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putchar('\n'); |
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} |
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|
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|
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#ifdef ENCRYPTED_PASSWORDS |
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/* |
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* Encrypt and Base64 encode passwords. Append the MD5 checksum of the |
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* passwords before encrypting them. |
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*/ |
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int |
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encrypt_passwords(FILE * fd, account_t ** accts) |
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{ |
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int i, n; |
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unsigned char iv[EVP_MAX_IV_LENGTH]; |
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unsigned char *key; |
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unsigned char buf[ENCRYPT_BUF]; |
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unsigned char ebuf[ENCRYPT_BUF]; |
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unsigned char bbuf[ENCRYPT_BUF]; |
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unsigned char mdv[EVP_MAX_MD_SIZE]; |
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int mdl, ebufl, bbufl; |
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EVP_CIPHER_CTX ctx; |
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EVP_MD_CTX mdctx; |
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EVP_ENCODE_CTX bctx; |
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|
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key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH); |
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|
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srandom(time(NULL)); |
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|
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/* Initialization vector. */ |
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n = 1 + random() % 100000000, 10; |
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snprintf(iv, EVP_MAX_IV_LENGTH, "%08d", n); |
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fprintf(fd, "%s\n", iv); |
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|
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EVP_CIPHER_CTX_init(&ctx); |
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|
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EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, |
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strlen(passphr), 1, key, NULL); |
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|
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EVP_DigestInit(&mdctx, EVP_md5()); |
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EVP_EncryptInit(&ctx, EVP_bf_cbc(), key, iv); |
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EVP_EncodeInit(&bctx); |
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|
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for (i = 0; accts[i] != NULL; i++) { |
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snprintf(buf, ENCRYPT_BUF, "%s %s %s\n", accts[i]->server, |
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accts[i]->user, accts[i]->pass); |
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EVP_DigestUpdate(&mdctx, buf, strlen(buf)); |
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EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf)); |
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EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl); |
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|
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fwrite(bbuf, sizeof(char), bbufl, fd); |
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} |
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|
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EVP_DigestFinal(&mdctx, mdv, &mdl); |
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|
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xstrncpy(buf, ".\n", ENCRYPT_BUF - 1); |
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|
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/* MD5 checksum of data. */ |
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for (i = 0; i < mdl; i++) |
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snprintf(2 + buf + i * 2, ENCRYPT_BUF - 3 - i * 2, "%02x", |
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mdv[i]); |
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|
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EVP_EncryptUpdate(&ctx, ebuf, &ebufl, buf, strlen(buf)); |
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EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl); |
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fwrite(bbuf, sizeof(char), bbufl, fd); |
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|
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EVP_EncryptFinal(&ctx, ebuf, &ebufl); |
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|
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EVP_EncodeUpdate(&bctx, bbuf, &bbufl, ebuf, ebufl); |
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fwrite(bbuf, sizeof(char), bbufl, fd); |
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|
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EVP_EncodeFinal(&bctx, bbuf, &bbufl); |
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fwrite(bbuf, sizeof(char), bbufl, fd); |
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|
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EVP_CIPHER_CTX_cleanup(&ctx); |
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|
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return 0; |
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} |
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|
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|
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/* |
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* Decode (Base64) passwords, decrypt them and verify the MD5 checksum. |
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*/ |
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int |
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decrypt_passwords(unsigned char **buf, FILE * fd) |
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{ |
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int i, j; |
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unsigned char iv[EVP_MAX_IV_LENGTH]; |
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unsigned char *key; |
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unsigned char *c; |
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unsigned char ebuf[LINE_MAX]; |
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unsigned char bbuf[LINE_MAX]; |
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unsigned char mdv[EVP_MAX_MD_SIZE]; |
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unsigned char mdc[EVP_MAX_MD_SIZE * 2 + 1]; |
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int mdl, bufl, ebufl; |
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EVP_CIPHER_CTX *ctx; |
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EVP_MD_CTX mdctx; |
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EVP_ENCODE_CTX bctx; |
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|
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j = 1; |
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|
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c = *buf = (unsigned char *)smalloc(DECRYPT_BUF * sizeof(char)); |
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key = (unsigned char *)smalloc(EVP_MAX_KEY_LENGTH); |
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ctx = (EVP_CIPHER_CTX *) smalloc(sizeof(EVP_CIPHER_CTX)); |
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|
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fgets(bbuf, LINE_MAX, fd); |
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|
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memcpy(iv, bbuf, EVP_MAX_IV_LENGTH); |
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|
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EVP_CIPHER_CTX_init(ctx); |
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|
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EVP_BytesToKey(EVP_bf_cbc(), EVP_md5(), NULL, passphr, strlen(passphr), |
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1, key, NULL); |
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|
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EVP_DecryptInit(ctx, EVP_bf_cbc(), key, iv); |
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EVP_DecodeInit(&bctx); |
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|
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while (fgets(bbuf, LINE_MAX, fd)) { |
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EVP_DecodeUpdate(&bctx, ebuf, &ebufl, bbuf, strlen(bbuf)); |
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if (!EVP_DecryptUpdate(ctx, c, &bufl, ebuf, ebufl)) |
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goto fail; |
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|
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c += bufl; |
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*c = '\0'; |
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|
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if (c - *buf > DECRYPT_BUF * j - 64) { |
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i = c - *buf; |
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*buf = (char *)srealloc(*buf, DECRYPT_BUF * ++j); |
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c = *buf + i; |
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*c = '\0'; |
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} |
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} |
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|
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EVP_DecodeFinal(&bctx, ebuf, &ebufl); |
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if (!EVP_DecryptFinal(ctx, c, &bufl)) |
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goto fail; |
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|
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c += bufl; |
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*c = '\0'; |
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|
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/* Calculate the MD5 checksum and check if it is correct. */ |
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if (!(c = strstr(*buf, "\n.\n"))) |
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goto fail; |
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|
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EVP_DigestInit(&mdctx, EVP_md5()); |
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EVP_DigestUpdate(&mdctx, *buf, c - *buf + 1); |
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EVP_DigestFinal(&mdctx, mdv, &mdl); |
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|
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for (i = 0; i < mdl; i++) |
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snprintf(mdc + i * 2, EVP_MAX_MD_SIZE * 2 + 1 - i * 2, "%02x", |
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mdv[i]); |
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|
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c += 3; |
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|
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if (strncmp(c, mdc, 32)) |
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goto fail; |
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|
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EVP_CIPHER_CTX_cleanup(ctx); |
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|
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sfree(key); |
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sfree(ctx); |
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|
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return 0; |
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|
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fail: |
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error("Wrong master passphrase.\n"); |
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EVP_CIPHER_CTX_cleanup(ctx); |
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sfree(*buf); |
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sfree(key); |
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sfree(ctx); |
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|
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return ERROR_DECRYPT; |
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} |
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|
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|
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/* |
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* Store encrypted passwords to file. |
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*/ |
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int |
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store_passwords(account_t ** accts) |
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{ |
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char pwfile[PATH_MAX]; |
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FILE *fd; |
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|
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snprintf(pwfile, PATH_MAX, "%s/%s", home, PATHNAME_PASSWORDS); |
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|
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create_file(pwfile, S_IRUSR | S_IWUSR); |
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|
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fd = fopen(pwfile, "w"); |
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|
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if (fd == NULL) |
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fatal(ERROR_FILEOPEN, "opening passwords file %s; %s\n", |
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pwfile, strerror(errno)); |
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|
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encrypt_passwords(fd, accts); |
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|
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fclose(fd); |
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|
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return 0; |
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} |
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|
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|
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/* |
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* Interactive encrypted passwords editor. |
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*/ |
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void |
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password_editor(void) |
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{ |
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int i, q, n, pn; |
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char buf[LINE_MAX]; |
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char *c; |
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char *p[2]; |
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account_t *a, **accts; |
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|
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if (!(flags & FLAG_BLANKPASS)) { |
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error("no candidate passwords for encryption found\n"); |
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return; |
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} |
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q = pn = 0; |
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|
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for (a = accounts; a != NULL; a = a->next) |
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if (a->pass_attr != PASS_ATTR_PLAIN) |
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pn++; |
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|
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accts = (account_t **) xmalloc((pn + 1) * sizeof(account_t *)); |
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|
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memset(accts, 0, (pn + 1) * sizeof(account_t *)); |
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|
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for (i = 0, a = accounts; a != NULL; a = a->next) { |
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if (a->pass_attr != PASS_ATTR_PLAIN) |
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accts[i++] = a; |
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} |
277 |
|
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do { |
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printf("cmd: "); |
280 |
fgets(buf, LINE_MAX, stdin); |
281 |
c = buf; |
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for (;; c++) { |
283 |
if (*c == ' ' || *c == '\t') |
284 |
continue; |
285 |
else if (*c == '?' || *c == 'h') |
286 |
printf("c\tclear a password entry\n" |
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"e\tedit a password entry\n" |
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"h\thelp\n" |
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"l\tlist entries\n" |
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"p\tchange master password\n" |
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"q\tquit without saving\n" |
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"w\tsave changes\n" |
293 |
"x\tsave and exit\n"); |
294 |
else if (*c == 'q') |
295 |
q = 1; |
296 |
else if (*c == 'l') |
297 |
for (i = 0; i < pn; i++) |
298 |
printf("%d %s %s %s\n", i + 1, |
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accts[i]->server, |
300 |
accts[i]->user, |
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accts[i]->pass); |
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else if (*c == 'e') { |
303 |
n = atoi(++c); |
304 |
if (n == 0 || n < 1 || |
305 |
n > pn || |
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accts[n - 1] == NULL) |
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break; |
308 |
accts[n - 1]->pass[0] = '\0'; |
309 |
printf("Enter new password: "); |
310 |
if (fgets(accts[n - 1]->pass, PASS_LEN, |
311 |
stdin) && |
312 |
(c = strchr(accts[n - 1]->pass, '\n'))) |
313 |
*c = '\0'; |
314 |
} else if (*c == 'c') { |
315 |
n = atoi(++c); |
316 |
if (n == 0 || n < 1 || |
317 |
n > pn || |
318 |
accts[n - 1] == NULL) |
319 |
break; |
320 |
accts[n - 1]->pass[0] = '\0'; |
321 |
} else if (*c == 'p') { |
322 |
p[0] = (char *)smalloc(PASSPHRASE_LEN); |
323 |
p[1] = (char *)smalloc(PASSPHRASE_LEN); |
324 |
do { |
325 |
for (i = 0; i < 2; i++) { |
326 |
printf("Enter %snew master " |
327 |
"password: ", |
328 |
i ? "again " : ""); |
329 |
get_password(p[i], |
330 |
PASSPHRASE_LEN); |
331 |
} |
332 |
} while (strcmp(p[0], p[1])); |
333 |
xstrncpy(passphr, p[0], PASSPHRASE_LEN - 1); |
334 |
sfree(p[0]); |
335 |
sfree(p[1]); |
336 |
} else if (*c == 'w' || *c == 's') { |
337 |
store_passwords(accts); |
338 |
} else if (*c == 'x') { |
339 |
store_passwords(accts); |
340 |
q = 1; |
341 |
} else |
342 |
break; |
343 |
} |
344 |
} while (!q); |
345 |
} |
346 |
#endif /* ENCRYPTED_PASSWORDS */ |